recap/Repeat or summarize what has been already said.
When you recapitulate, you repeat or a give a summary of what has already been said or decided. When we narrate a story in parts, we recapitulate, before we begin every new part, the earlier part of the story, by giving a brief summary of those parts. In TV serials too, there is a brief repetition of the earlier episode before a new episode begins.

The first half of every episode in almost every TV serial is just a recapitulation of the earlier episodes. This repetition of the earlier episodes gives the producers an opportunity of prolonging the serial.

At the beginning of every book of the English epic Paradise Lost we have a recapitulation of the earlier books. Milton repeats briefly the story covered in the earlier books.